Component Carrier Interconnection and Manufacturing Method

Abstract

A component carrier assembly includes a first component carrier having a first electrically insulating layer structure and a via in the first electrically insulating layer structure, where the via is at least partially filled with electrically conductive material and where an upper part of the via extends beyond an outer main surface of the first component carrier; and a second component carrier having a second electrically insulating layer structure, and an electrically conductive adhesive material that is at least partially embedded in the second electrically insulating layer structure. The first component carrier and the second component carrier are interconnected and the upper part of the via at least partially penetrates into the electrically conductive adhesive material.

Claims

1. A component carrier assembly, comprising: a first component carrier, having: a first electrically insulating layer structure, and a via in the first electrically insulating layer structure, wherein the via is at least partially filled with electrically conductive material, and wherein an upper part of the via, in particular comprising at least a part of the electrically conductive material, extends beyond an outer main surface of the first component carrier; a second component carrier, having: a second electrically insulating layer structure, and an electrically conductive adhesive material that is at least partially embedded in the second electrically insulating layer structure; wherein the first component carrier and the second component carrier are interconnected, in particular stacked; and wherein the upper part of the via at least partially penetrates into the electrically conductive adhesive material.

2. The component carrier assembly according to claim 1, wherein the upper part of the via is immersed, in particular completely immersed, into the electrically conductive and adhesive material.

3. The component carrier assembly according to claim 2, wherein the outer main surface of the first component carrier and a further outer main surface of the second component carrier are directly connected, in particular flush.

4. The component carrier assembly according to claim 1, wherein the electrically conductive adhesive material comprises a paste, in particular a sintering paste.

5. The component carrier assembly according to claim 1, wherein the via is one of the group which consists of a blind via, a through via, a laser via, a mechanically drilled via, a completely filled via, a copper pillar, a round via, a rectangular via, a tapered via.

6. The component carrier assembly according claim 1, wherein the upper part of the via comprises an electrically conductive pad, in particular wherein the upper part is broader than other parts of the via.

7. The component carrier assembly according to claim 1, wherein the first component carrier further comprises: a first electrically conductive layer structure in and/or below the first electrically insulating layer structure, wherein the via electrically contacts the first electrically conductive layer structure; and/or wherein the second component carrier further comprises: a second electrically conductive layer structure in and/or below the second electrically insulating layer structure, wherein the electrically conductive adhesive material electrically contacts the second electrically conductive layer structure.

8. The component carrier assembly according to claim 7, wherein the first electrically conductive layer structure is electrically connected to the second electrically conductive layer structure through the via and the electrically conductive adhesive material.

9. The component carrier assembly according to claim 1, wherein the first component carrier and/or the second component carrier comprises a layer stack.

10. The component carrier assembly according to claim 1, wherein the first electrically insulating layer structure and/or the second electrically insulating layer structure comprises a resin layer or a prepreg layer, in particular one of the group which consists of epoxy resin, bismaleimide-triazine resin, FR-4, FR-5, cyanate ester resin, polyphenylene derivate, glass, prepreg material, polyimide, polyamide, liquid crystal polymer, epoxy-based build-up film, polytetrafluoroethylene, a ceramic, a metal oxide.

11. A method of manufacturing a component carrier assembly, the method comprising: providing a first component carrier with at least one first electrically insulating layer structure; forming a first cavity in the at least one first electrically insulating layer structure; at least partially filling the first cavity with electrically conductive material to obtain a via; forming an upper part of the via, in particular comprising at least a part of the electrically conductive material, that extends beyond an outer main surface of the first component carrier; providing a second component carrier with at least one second electrically insulating layer structure; forming a second cavity in the at least second electrically insulating layer structure; filling the second cavity at least partially with electrically conductive adhesive material; interconnecting, in particular stacking, the first component carrier and the second component carrier, thereby penetrating the upper part of the via at least partially in the electrically conductive adhesive material.

12. The method according to claim 11, wherein filling the via further comprises: forming an electrically conductive layer on the outer main surface of the first electrically insulating layer; and structuring the electrically conductive layer, in particular using photo-imaging, to obtain the upper part.

13. The method according to claim 11, wherein stacking comprises laminating, in particular by using temperature and pressure.

14. The method according to claim 11, wherein the method further comprises: hardening, in particular sintering, the electrically conductive adhesive material.

15. A method for connecting first and second component carriers, the method comprising: using a copper via that protrudes from a first component carrier as an anchor; immersing a portion of the copper via that protrudes from the first component carrier in a sintering paste of a second component carrier; and sintering the paste to interconnect the component carriers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] FIG. 1 illustrates a side view of a component carrier assembly according to an exemplary embodiment of the disclosure.

[0071] FIG. 2A and FIG. 2B illustrate a prior art example of connected circuit boards.

[0072] FIG. 3A, FIG. 3B, FIG. 3C, FIG. 3D, FIG. 3E, FIG. 3F, FIG. 3G, FIG. 3H, FIG. 3I, FIG. 3J and FIG. 3K illustrate a method of manufacturing a component carrier assembly according to an exemplary embodiment of the disclosure.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

[0073] The illustrations in the drawings are schematically presented. In different drawings, similar or identical elements are provided with the same reference signs.

[0074] Before, referring to the drawings, exemplary embodiments will be described in further detail, some basic considerations will be summarized based on which exemplary embodiments of the disclosure have been developed.

[0075] According to an exemplary embodiment, a copper via is immersed in sintering paste to create a mushroom-like via, including for example a normal laser via capped with sintering paste. This enables greater shift compensation, reduces the need for expensive sintering paste and increases the pure copper content of the Z-axis connection. The immersion of the copper via into the paste creates a higher reliability. An electrical connection is created by sintering the paste (and melting the resin sheet). Thus, a Z-axis connection is created by a combination of a copper via and a cap based on sintering paste.

[0076] FIG. 1 illustrates a component carrier assembly 100 according to an exemplary embodiment of the disclosure.

[0077] The assembly 100 comprises a first component carrier 110, having a first electrically insulating layer structure 115, and a via 120 formed in the first electrically insulating layer structure 115. The via 120 is (completely) filled with electrically conductive material. An upper (extended) part 121 of the via 120 extends beyond an outer main surface 111 of the first component carrier 110. The first component carrier 110 further comprises a first electrically conductive layer structure 116 in (at the bottom of) the first electrically insulating layer structure 115, wherein the via 120 electrically contacts said first electrically conductive layer structure 116. The first electrically insulating layer structure 115 is arranged on a first substrate 117, e.g., a further layer stack.

[0078] The assembly 100 further comprises a second component carrier 130, having a second electrically insulating layer structure 135, and an electrically conductive adhesive material 140 that is embedded in the second electrically insulating layer structure 135. The second component carrier 130 further comprises a second electrically conductive layer structure 136 in (at the bottom of) the second electrically insulating layer structure 135, wherein the electrically conductive adhesive material 140 electrically contacts the second electrically conductive layer structure 136. The second electrically insulating layer structure 135 is arranged on a second substrate 137, e.g., a further layer stack.

[0079] The first component carrier 110 and the second component carrier 130 are stacked in the Z-direction (parallel to the Z-axis, and perpendicular to the directions of main extension (x, y) of the component carriers 110, 130) and interconnected by the upper part 121 of the via 120 that penetrates into the electrically conductive adhesive material 140 (thereby functions as an anchor). In particular, the upper part 121 of the via 120 is completely immersed into the electrically conductive and adhesive material 140. The outer main surface 111 of the first component carrier 110 and a further outer main surface 131 of the second component carrier 130 are directly connected and flush with each other.

[0080] The upper part 121 of the via 120 comprises an electrically conductive pad, wherein the upper part 121 is broader than the other parts of the via 120. The first electrically conductive layer structure 116 is electrically connected to the second electrically conductive layer structure 136 through the via 120 and the electrically conductive adhesive material 140.

[0081] FIG. 3A to FIG. 3K illustrate a method of manufacturing a component carrier assembly according to an exemplary embodiment of the disclosure.

[0082] As illustrated in FIG. 3A, a first component carrier 110 is provided with at least one first electrically insulating layer structure 115. First electrically conductive layer structures 116 are embedded at the bottom of the first electrically insulating layer structure 115 and directly on top of a first substrate 117 of the first component carrier 110. Further, an electrically conductive layer 125 is formed on the outer main surface 111 of the first electrically insulating layer 115.

[0083] In FIG. 3B and FIG. 3C a first cavity 122 is formed in the first electrically insulating layer structure 115 and through the electrically conductive layer 125 using laser drilling.

[0084] As shown in FIG. 3D, the first cavity 122 is filled with electrically conductive material to obtain a via 120 (e.g., by plating). Thereby, the thickness of the electrically conductive layer 125 is increased.

[0085] In FIG. 3E, a photo-imageable dielectric (PID) layer 126 (or other exposable resist) is applied on top of the electrically conductive layer 125. A lithographic process is carried out for forming a structure which covers the via 120 (and is then developed).

[0086] As illustrated in FIG. 3F, the electrically conductive layer 125 is structured after developing the exposable resist using subtractive etching process so that only the expanded part 121 of the via remains. The rest of the PID layer 126 is then stripped.

[0087] In FIG. 3G a first component carrier 110 with a first electrically insulating layer structure 115 and an embedded via 120 is provided, wherein the upper part 121 of the via 120 extends beyond the outer main surface 111 of the first electrically insulating layer structure 115 and of the first component carrier 110.

[0088] In FIG. 3H a second component carrier 130 with at least one second electrically insulating layer structure 135 is provided. Second electrically conductive layer structures 136 are embedded at the bottom of the second electrically insulating layer structure 135 and directly on top of a second substrate 137 of the second component carrier 130.

[0089] In FIG. 3I a second cavity 142 is formed in the at least one second electrically insulating layer structure 135 using laser drilling.

[0090] In FIG. 3J the second cavity 142 is filled with electrically conductive adhesive material 140, for example a sintering paste. The electrically conductive adhesive material 140 is embedded in the second component carrier 130 and flush with a further outer main surface 131 of the second component carrier 130.

[0091] Lastly, in FIG. 3K the first component carrier 110 and the second component carrier 130 are stacked in the Z-direction, so that the protruding upper part 121 of the via 120 penetrates into the electrically conductive adhesive material 140 and thereby forms an anchor structure. The stacking comprises laminating using temperature and pressure. The component carrier assembly 100 is now interconnected in a robust manner by hardening (in particular sintering) the electrically conductive adhesive material 140.

[0092] It should be noted that the term “comprising” does not exclude other elements or steps and the “a” or “an” does not exclude a plurality. Also, elements described in association with different embodiments may be combined.

[0093] Implementation of the disclosure is not limited to the preferred embodiments shown in the figures and described above. Instead, a multiplicity of variants is possible which variants use the solutions shown and the principle according to the disclosure even in the case of fundamentally different embodiments.

REFERENCE SIGNS

[0094] 100 Component carrier assembly [0095] 110 First component carrier [0096] 111 Outer main surface [0097] 115 First electrically insulating layer structure [0098] 116 Second electrically conductive layer structure [0099] 117 First substrate [0100] 120 Via [0101] 121 Upper, extended part of via, conductive trace [0102] 122 First cavity [0103] 125 Electrically conductive layer [0104] 126 Photo-imageable dielectric layer [0105] 130 Second component carrier [0106] 131 Further outer main surface [0107] 135 Second electrically insulating layer structure [0108] 136 Second electrically conductive layer structure [0109] 137 Second substrate [0110] 140 Electrically conductive adhesive material sintering paste [0111] 142 Second cavity [0112] 200 Prior art circuit boards [0113] 210 Prior art first circuit board [0114] 230 Prior art second circuit board [0115] 240 Prior art sintering paste layer